Kataline Petrova. The twin of the oh so famous Katherine Pierce, aka Katarina Petrova.
Both Katherine and Kataline are greeted by the handsome Salvatore brothers, each taking a liking to each sister. There's only one difference between them. Kataline is human. Katherine is a vampire. They've kept it a secret for generations. A witch has created a spell for Kataline so she may live alongside her sister, without ever aging.
Enjoying the company of the Salvatore brothers, terror struck and suddenly everyone is after vampires. The group of vampire hunters, lead by Johnathan Gilbert, has found out about vampires and wants to get rid of them once and for all.
Btw there will be a time skip to the present times of where the vampire diaries takes place.